The present invention relates generally to compositions and methods for treating fuel hydrocarbons; more particularly, to the incorporation of a visibility enhancing amount of at least one fluorescent type compound effective to permit visualization or tracing of said composition in low light or no light conditions; and most particularly to compounds for providing an ability to visualize compositions utilized for treating fuel hydrocarbons at levels of light otherwise insufficient for such visualization, and to further determine the authenticity of a particular treating composition.
1. Background of the Invention
It has been established that fire suppression agents can be extremely beneficial in effectively quenching fires of various types and eliminating their ability to reignite (U.S. Pat. Nos. 5,945,026 and 6,139,775 to Thames.) According to these patents, a particularly disclosed class of compositions are shown to be useful for application to either surface or subsurface concentrations of hazardous or undesirable hydrocarbons, including masses of gasoline, oil and the like that are spilled on land, and which are intentionally or unintentionally disposed of in sewers, exposed to the soil or the air, or the like as the result of an accident of some sort. Chemical breakdown of the dispersed hydrocarbons can be accelerated by increasing the concentration of available bacteria for this purpose. In some cases, the surface active agent (xe2x80x9csurfactantxe2x80x9d) composition itself can serve as a nutrient for the bacteria, thus enhancing its action in degrading the hydrocarbon materials.
In the past, the concept of utilizing surface active agents in water for treating fires has often been suggested. One aspect of the use of surfactants in firefighting is that such treatment can render the water xe2x80x9cwetter,xe2x80x9d i.e., better able to penetrate into and through the surfaces of semi-solid materials. Moreover, the ability of surfactant materials to create frothing or foaming has been used in an attempt to provide a barrier at the liquid-air interface, which barrier will block oxygen from access to vapor at the liquid surface, usually the surface of a mass of burning oil or gasoline. In this connection, it is well known that, particularly in a petroleum-based fire, the combustion occurs only in the vapor phase, wherein oxygen in large quantities is readily available to the vapors originating within the liquid. In a fire, the increase in temperature accelerates the liquid vaporation and hence the rate of combustion. In many instances, surface active agents, particularly when accompanied by agitation, serve to achieve a mix of liquid water and fuel, thus rendering the fuel less volatile and less susceptible to burning.
However, when combining an agent with the turbulent stream of firefighting water under high pressure, there are limited ways to ensure the adequate coverage of a fire suppressing agent, particularly in conditions where the amount of ambient light is limited. In addition, there are no practical methods available to ensure the authenticity of a stored agent, nor are these effective means for quantifying variable constituents.
2. Description of the Prior Art
U.S. Pat. Nos. 5,945,026 and 6,139,775 issued to Thames relate to a biodegradable, non-toxic firefighting concentrate composition diluted with water and effective when mixed with foam-forming materials. The concentrate is extremely useful in aquatic and land fires. Although the composition in U.S. Pat. No. 5,945,026 does incorporate a dye for visualizing and detecting the coverage of a firefighting agent when combined with other firefighting means, it is effective merely for identification purposes when viewed in sufficient ambient light. There is no suggestion to utilize a fluorescent dye for any purpose whatsoever.
U.S. Pat. No. 6,065,545 to Williams teaches a method and composition for extinguishing fires. The composition involves the use of a visual coloration added to a firefighting agent to detect its presence in ambient light when thrown in a fluid stream comprising fluid and/or foam. However, there is no suggestion disclosed for incorporating the use of a fluorescent dye as a means of visualization other than in lighting conditions sufficient to be easily viewed within the stream of fluid or foam.
U.S. Pat. No. 5,990,486 issued to Chen et al. teaches an apparatus and method for measuring components of a solute stream. The method is accomplished by measuring a concentration of an indicator agent comprising a water soluble or water insoluble dye, specifically claiming rubrene, rhodamine B, or fluorescein or a salt thereof. The solute stream may contain an aqueous film-forming foam. One advantage suggested is that the indicator agents provide greatly increased visibility for the fluid streams in which they are introduced, e.g., enhanced visibility of fire hose stream water or nighttime or other dark situation firefighting applications. Light capable of detecting the indicator agent, e.g., incandescent or ultraviolet (UV) light, can illuminate the liquid at a predetermined reference point. Chen et al. discloses the addition of a fluorescent dye to a stream containing a firefighting additive, e.g., a stream emanating from a fire hose nozzle. The dye is incorporated as a means of for aiding in quantifying the total concentration of the solute, or firefighting agent, and as a means of enhancing visibility of the liquid stream.
There are a multitude of instances when extremely low levels of ambient light make it difficult or impossible to visualize firefighting materials, particularly when the concentration is substantially reduced by foaming of the composition. Low-level light situations include examples such as a fire within a structure without exposure to natural light (i.e. the hull of a ship), a forest fire at night, or any type of situation where the coverage of active agent must be ascertained in the dark.
The present invention is directed to the incorporation of fluorescent type compounds that are useful for providing increased visualization of fire suppression agents when used to fight fires at levels of light insufficient to enable visualization of a fire suppressant agent, to provide tracing capability to a bio-remediation project, or as a quick reference for security purposes to determine if the product is genuine or counterfeit.
Fluorescent dyes are commonly employed to impart both visible color and fluorescence to other materials to enhance visualization, for example, imaging agents, leak detection, detecting impurities, and the like. Types of dyes typically utilized for visual enhancement are fluoresceins, multi-fluoresceins, rhodamines, pyrenes, etc. Inclusion of such dyes provides a useful addition to methods and compositions of firefighting agents.
High visibility fluorescent dyes that are fluorescent in the visible (400-700 nanometers) spectrum and ultraviolet compounds/dyes, active in the 200-400 nanometer wavelength spectrum, can be used for these purposes. Physical requirements of these compounds include a need to be infinitely dispersible, soluble, or miscible in a water-based system. Although not wishing to be limited to a particular dye, examples of those useful in the present invention are monoazo dyes, such as monoazo xanthene, monoazo anthraquinone, monoazo stilbene, and combinations thereof.
An ultraviolet dye or compound that is active in the 200 to 400 nanometer range can be added in trace amounts to firefighting formulations such that the compound itself is invisible to the unaided eye but exhibits a strong absorbance at specific wavelengths in the Ultraviolet spectrum. Such compounds can be seen on an Ultraviolet/Visible Spectrophotometer as a very sharp peak of absorbance at a very specific wavelength.
Accordingly, it is an objective of the invention to provide a foam composition exhibiting an enhanced degree of visibility.
Another objective of the invention is to provide a composition including at least one fluorescent type compound which enhances visibility while not impairing the functionality of the end product.
A further objective of the invention is to provide a fluorescent type compound useful as an aid for security purposes to determine the authenticity of the product, e.g., a firefighting product.
Yet another object of the invention is to provide a composition for use in a bio-remediation project including a fluorescent type compound with tracing capability.
Another object of the invention is to provide a fluorescent type compound which is biodegradable and non-toxic.